Apparatus for uncurling the edges of a fabric web

ABSTRACT

At least one rotatable contact plate is arranged with part of its periphery in contact with the underside of the fabric web. Mechanism is provided for driving the contact plate from below and a cover member lies on the edge of the web above the contact plate to hold the web against the contact plate and to serve as a safety protector.

United States Patent 1191 Becker 1 Apr. 29, 1975 [54] APPARATUS FOR UNCURLING THE EDGES 2.650 113 9/1953 Pope et a1. H 26/D1G, l UX OF A FABRIC WEB 2.813.325 11/1957 Quick ct 211. 1. 26/DIG. 1 UX 2.942.322 6/1960 Howitt 1. 26/D1G. l UX [75} Inventor: Arno Becker, Freudens l 3.271.889 9/1966 L0ng,Sr1 w. 26/DIG. 1 UX Germany 3.335.474 8/1967 Cho M 26/66 X [73] Assignee: Bruckner Trockentechnik KG, FOREIGN PATENTS OR APPLICATIONS Leonbefg Germany 500.954 9 1930 Germany 26/010. 1

- 1,428 1864 United Kingdom 1 1 1. 139/294 1221 1973 162.028 4/1921 United Kingdom 26/016. 1 [211 App]. No.: 349,934

Primary Examiner-Robert R. Mackey [30] Foreign Application Priority Dam Attorney, Agent. or Firm-Marshall 8L Yeasting '1 i 7 Apr. 27, 197- German -220606 S R C [52] US, Cl, 215/54; 26/D|G 1; 26/66 At least one rotatable contact plate is arranged with 1511 1111. (:1 D06c 3/06; D06c 25/00 p of its periphery in Contact with the underside of 53 Fi |d f Search H 2 /910 66 54; the fabric web. Mechanism is provided for driving the 139/294, 295, 296; 38/143 contact plate from below and a cover member lies on the edge of the web above the contact plate to hold [56] References Ci d the web against the contact plate and to serve as a UNITED STATES PATENTS 543.482 7/1895 Hohrath 26/DlG 1 ux 4 a s. 2 Dra ing Figures APPARATUS FOR UNCURLING THE EDGES OF A FABRIC WEB BACKGROUND OF THE INVENTION This invention relates to a device for flattening the edge of a web of fabric at the entrance to a treatment device for outspread webs, especially for knitted fabric webs, with at least one rotating contact plate having part of its periphery in contact with the fabric web.

It very frequently happens (especially with knitted fabric) that outspread webs of fabric, which on feeding into a treatment device, for instance, a tenter or calender, have curled-up longitudinal edges. Various devices for flattening the web edges have been developed to prevent these curled-up edges of the fabric from interfering with the operation of devices for treating the fabric webs.

Thus one device is known wherein two gripping strips endlessly circulating in the style of the conveyor belt are provided above and below the web being moved. The direction of movement of the two oppositely operating but cooperating strips is generally perpendicular to the direction of movement of the fabric web. The arrangement and construction of the flattening strips produces a braking effect on the web, which has an extremely disadvantageous effect, especially for high web speeds, and also for delicate fabrics (e.g., knitted).

Devices are also known with flattening fingers which have a threaded periphery and act in opposition to the direction of conveyance of the web. Since this type of flattening finger has a relatively small area of contact with the fabric web, the fingers have to be pressed relatively hard against the web, and this again means that the web is braked, and these contra-rotating flattening fingers stretch the edge of the fabric in an undesirable manner.

Finally a further known device for flattening an edge of a fabric web has two contact plates whose free end faces lie opposite each other, have roughened conical contact surfaces, and cooperate in such manner that during their rotation they engage the web edge with part of their periphery somewhat in jaw fashion. The curled-up fabric edge should then be smoothed or flattened. This known device can admittedly be used with relatively good success on insensitive fabric webs (e.g., cotton fabrics), but is quite unsuitable if the edges of elastic fabric webs, e.g., knitted fabrics, are to be flattened, since the two peripheral portions of the superimposed contact plates cannot readily be adjusted to the individual web thickness and to the size of the curledup edge. In practice the position of these two contact plates relative to each other must be very frequently changed. Because of the awkwardness of this operation, it is usually neglected, so that with delicate elastic fabric webs the edges are either not properly flattened or are stretched to an undesirable degree. Also since the two contact plates are disposed in a jaw-shaped gear casing, a relatively crude and large construction results, which is very awkward and has an even dangerous effect at the entrance to treating machines, such as stretching devices or the like.

SUMMARY OF THE INVENTION The invention is therefore aimed at the problem of providing a device of the type hereinbefore described which firstly ensures extremely gentle flattening of the edge of a fabric web even with very delicate elastic fabrics, and secondly can be disposed in a compact assembly directly at the entrance to the web treating devicev According to the invention this problem is solved in that a contact plate disposed in the area of the underside of the fabric web, and driven from below, cooperates with a cover member lying on the web and also serving as a safety protector.

The present invention is based on the recognition that if the fabric web is to be applied to a tenter chain for feeding into a treatment device, the curled-up edge of the web preferably lies below the tenter chain, since otherwise the flattened edge would stand up in the needles.

With the construction provided by the invention, it is therefore sufficient to put the contact plate only at the underside of the web; the curled-up web edge is in any case very gently flattened, with the cover member lying above the web only pressing it against the contact plate to a reasonable extent, so that proper flattening of the web edge is always ensured. This is also aided by the relatively large area of contact between the web and the contact plate.

Because of the shape of the plate and its disposition at the underside of the web, the device provided by the invention can be mounted relatively close to the inlet rollers of the treating device. This ensures that the web is fed fully flattened into the roller gap, and also ensures a compact arrangement at the entrance to the treating device. The cover member lying on the web also extends close to the inlet gap of the said rollers, and in particular the complete covering of the flattening members almost completely precludes the risk of accidents which might occur in the zone of the roller inlet gap and at the contact plates.

The cover member is preferably formed as a smoothsurfaced lid lying loosely on the fabric web, so that no braking effect is produced on the web, and the web is only pressed very gently against the contact plate. The construction of part of the cover member as a folding lid, and the complete absence of disturbing superstructures makes the introduction of the start of a new web considerably easier. If in accordance with a further development of the invention the contact plate is formed as a flat frusto-conical plate with a gripping upper surface, and this upper surface is provided with teeth inclined to the central axis of the plate, it is impossible for the web to stick to the contact plate.

A further advantageous form of the invention is provided if the contact plate can be raised relative to the web. In this manner effective flattening of the edges can be achieved even for less delicate webs with extensively curled-up edges.

If, however, a sensitive elastic web has extensively curled-up edges, these can be reliably flattened by providing several contact plates substantially in sequence in the direction of transport of the fabric web.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical section through the entrance portion of a fabric web treating device, in which the device provided by the invention is incorporated;

FIG. 2 is a plan view of the device shown in FIG. I, seen in the direction of the arrow ll.

DESCRIPTION OF THE PREFERRED EMBODIMENT The device shown in the drawings for flattening the edge of a fabric web is at the entrance of a treating device, wherein after flattening of its longitudinal edges the web is, for instance. mounted on the needles of a tenter chain.

The flattening device 1 for a fabric web 2, which is conveyed in the direction of arrow 3, is disposed generally between a spreader roller 4 and a fabric pulling roller 5, located in front of the tentering means (not shown). In the embodiment shown. three contact plates 6, 6a, 6b formed as flat frusto-conical plates, are provided in sequence in the general direction of travel of the web (arrow 3). In order to produce a gripping upper surface, the contact plates 6, 6a, 6b each have teeth, and the teeth of each plate are inclined to the central axis 7 of that plate (see arrow 8 in FIG. 1). As seen especially from FIG. 1, all the contact plates. formed as toothed plates, are assembled in a common drive system 9, and are driven by a motor 10 having a belt transmission to one toothed plate 6, while the other plates 6a and 6b are set in rotation by this driven plate.

In order that these toothed plates 6, 6a, 6b with their frusto-conical form may have the maximum possible area of contact with the web 2, their central axes 7 are disposed at an angle differing from 90 in dependence on the chosen cone inclination in relation to the direction of web movement (arrow 3) so that, as seen from FIG. 1, at the time of contact the part of the disc surface lying nearest to the fabric pulling roller 5, and hence the peripheral portion in contact with the fabric web, is nearly or completely parallel to the web 2. The direction of rotation of the toothed plates 6. 6a, 6b is obviously so chosen that the web edge is flattened outwards (see FIG. 2, arrow ll). Depending on the arrangement of the teeth on the upper surface of the plate (for instance running radially or passing the central axis of the plate) and on the position of the toothed plate below the web, a flattening force is produced which either acts generally perpendicularly to the web edge or has a component in the direction of web movement, so that in neither case is there any braking effect on the web 2.

Together with its drive system, the entire flattening device 1 is held on an adjustment spindle 12 whereby the device can be set in accordance with the width of the web. a feeler 13 also being provided to produce automatic control. The support for the flattening device I provided by the invention is also adapted to permit lifting of the toothed plates 6, 6a, 6b relative to the web 2. If required a firmer engagement of the plates against the underside of the web can thus be produced, this again leading to a more powerful flattening effect.

An important feature for the good functioning of the device provided by the invention is however the cover member formed as a flat lid 14, which lies relatively loosely on the fabric web 2 and cooperates with the toothed plates 6, 6a, 6b. In the embodiment shown (see especially FIG. 1), this lid 14 has a smooth surface and is provided with an easily lifted edge. Thus the lid 14 can press the web travelling in the direction of arrow 3 loosely against the toothed plates 6, 6a, 6b in the desired manner, without producing any deleterious braking effect on the web movement.

At the same time the lid 14 covers the toothed plates 6, 6a. 6b so that they can operate while protected from accidents. If the flattening device is disposed before the entry gap of squeezing rollers or the like, the lid 14 also helps to ensure that this entry gap is safe from accidents, at least in the area of the web edges.

In order firstly to permit good support of the lid 14 on the web 2, and secondly to make the toothed plates 6, 6a, 6b accessible from above, it is desirable that the lid [4 covering the plates be at least in part pivotable. For this purpose the lid 14 has hinges l5, l5 seen in FIG. 2, by means of which the portion of the cover 14 that rests upon the fabric web is hinged to a fixed portion of the cover.

The pressure of the lid 14 on the web 2 is determined by the weight of the lid.

As seen from the preceding description, the construction in accordance with the invention provides an extremely compact and space-saving device for the flattening of fabric web edges, whose toothed plates by virtue of their flat construction and intermeshed arrangement (see FIG. 1) can be placed very close to the entry gap between the fabric pulling roller 5 and the web 2. The intensity of the flattening effect can be very finely matched to the specific requirements.

Finally it should be mentioned that while the drawings show only one flattening device for one fabric web edge 2', a second flattening device formed as a mirror image of the device shown is disposed at the other edge of the web.

I claim:

1. Apparatus constructed to fit close to an inlet roller of a fabric treating device, for gently unrolling a downwardly curled edge ofa fabric web without exerting any appreciable pull on the web, comprising a plurality of overlapping rotatable, driven contact discs arranged beneath each edge of the web,

each of said contact discs having a relatively flat frusto-conical upper surface,

the axis of each contact disc being located closely adjacent to the corresponding edge of the web, and forming an acute angle with the forward-extending portion of the web,

the forward half of each disc being substantially tangent to the web along the edge of the web,

and a member which gently holds the web down against the forward half of each disc, consisting of a cover mounted on hinges located substantially in the plane of the web and resting on the web above the discs.

2. A device according to claim 1 wherein the cover member comprises a portion having a flat undersurface resting loosely upon the fabric web.

3. A device according to claim 1 wherein the upper surface of each contact disc has teeth which are inclined to the central axis of the disc.

4. A device according to claim 1 comprising a common drive system for the contact discs at each edge of the web. 

1. Apparatus constructed to fit close to an inlet roller of a fabric treating device, for gently unrolling a downwardly curled edge of a fabric web without exerting any appreciable pull on the web, comprising a plurality of overlapping rotatable, driven contact discs arranged beneath each edge of the web, each of said contact discs having a relatively flat frustoconical upper surface, the axis of each contact disc being located closely adjacent to the corresponding edge of the web, and forming an acute angle with the forward-extending portion of the web, the forward half of each disc being substantially tangent to the web along the edge of the web, and a member which gently holds the web down against the forward half of each disc, consisting of a cover mounted on hinges located substantially in the plane of the web and resting on the web above the discs.
 2. A device according to claim 1 wherein the cover member comprises a portion having a flat undersurface resting loosely upon the fabric web.
 3. A device according to claim 1 wherein the upper surface of each contact disc has teeth which are inclined to the central axis of the disc.
 4. A device according to claim 1 comprising a common drive system for the contact discs at each edge of the web. 